A looped material band is defined as a flat strip whose ends have been assembled in order to form an endless loop. These looped material bands are used in many areas of industry as conveying elements such as a conveyor belt, a conveyor, but also as transmission elements such as a belt or similar.
Today various reversible or dismountable assembling systems for the ends of a conveyor belt exist, which allow advantageously installing such a band on a machine, replacing it, etc., without having to disassemble the machine and without the possible intervention of the manufacturer of the conveyor belt.
A solution described in document EP 1.085.120 provides junction means including a plurality of aligned eyelets, which are attached to the ends of a conveyor belt by means of staples or similar and assembled by means of a transversal rod.
Another assembly system known from document DE 4.442.927 is based on the presence of teeth integrated in the plane of the ends of a conveyor belt. The teeth are intended for being fitted into each other and are all provided with a metallic insert in which at least one assembly rod is screwed.
Such assembly means, which use essentially metallic elements, weaken the assembled ends, which are subjected to high tensions. Furthermore, these rigid metallic elements may create hazardous areas where operators and/or conveyed products may get caught. Another disadvantage is due to the fact that their presence increases the size of the conveyor belt and, consequently, the diameter when it winds around the driving rollers.
Another solution described in publication WO 2007/090148 consists in adding at each end of a conveyor belt, junction means including band sections showing serrations with complementary shapes. After fitting the serrations, one or more transversal rods passing through openings provided in each of the teeth contribute to locking the assembly. Removing the rods allows dismounting the conveyor belt. One of the disadvantages of such a configuration is due to the fact that the junction means must be connected by welding or by any similar process to the ends of the band, which leads eventually to a conveyor band having three assembly areas defining three areas of potential fragility. Furthermore, such junction means are not totally satisfactory when they are applied to bands with a reinforced structure. In fact, such an assembly system is elastic and lengthens with time. Regarding the toothed or timing belts with a positive drive, it has been noted that the pitch of the teeth lengthens locally, leading with time to a bad meshing with the pulleys. On the other hand, such junction means must imperatively be manufactured specifically for each type of conveyor belt, so that their respective features, in particular regarding the thickness, the material, the color or the possible presence of a traction core correspond. This imperative requirement is a major constraint for the conveyor belt manufacturer, who can become unable to foresee the costs and deadlines for his own customers. He is indeed subjected to the risks due to the procurement of suitable junction means, which are themselves supplied by the manufacturer of the raw material of the conveyor belt. In addition, the manufacturing process of such junction means, in which the openings for the passage of the assembly rods are drilled in the thickness of the teeth, is not only particularly tedious and delicate to carry out, but it furthermore does not allow to guarantee their perfect alignment, which is necessary for an easy and proper positioning of the rods.